PASTEURELLA

Question 1

Describe the Genus Pasteurella according to oxygen requirement.

Answer 1

Aerobic to microaerophilic or facultative anaerobic

Question 2

What is the type species of Genus Pasteurella?

Answer 2

P. mutocida

Question 3

Species of Pasteurella that causes septicemia in ducks and fowl and is listed as species incertae sedis (correct affliation yet uknown)

Answer 3

P. anatipestifer

Question 4

Based on DNA homology, the Genus Pasteurella comprises atleast how many species?

Answer 4

11

Question 5

Genus Pasteurella is motile. True or False?

Answer 5

False

Question 6

Genus Pasteurella is usually oxidase and catalase positive. True or False?

Answer 6

True

Question 7

Species of Pasteurella that are important pathogens of domestic and wild animals

Answer 7

1. P. multocida
2. P. haemolytica

Question 8

P. multocida causes what clinical disease in cattle and birds?

Answer 8

Causes primary septicemia in cattle and in domestic and wild birds, also an opportunistic invader of the respiratory tract of a variety of animals

Question 9

Give the clinical diseases induced by P. haemolytica. (in cattle and in sheep)

Answer 9

• Primary and opportunistic respiratory pathogen of cattle and sheep, causing septicemia and mastitis in sheep

Question 10

P. _____ and to a lesser extent, P. _____ are key constituent of shipping fever complex in cattle

Answer 10

haemolytica; multocida

Question 11

Other name of P. multocida

Answer 11

P. gallicida

Question 12

Give the morphology and staining features of P. multocida.

Answer 12

• Tiny, ovoid rods approx. 0.3 um x 0.4-0.8 um
• Stained films from tissue shows distinct bipolar appearance, not so with organism from culture
• Gram negative, non-sporeforming rods
• Many with capsular material when freshly isolated but quickly lost
• No flagella or pili

Question 13

Describe the colonies of P. multocida.

Answer 13

• Colonies on BAP are smooth, butyrous, convex and about 1-2 mm in diameter with a characteristic “mousy” odor due to metabolic products
• Slight greenish haze on BAP

Question 14

P. multocida does not liquefy gelatin. True or False?

Answer 14

True

Question 15

P. multocida produces indole. True or False?

Answer 15

True

Question 16

P. multocida reduces nitrate to nitrite. True or False?

Answer 16

False

Question 17

The seven biotypes or biovars are based on ?

Answer 17

Fermentation of sugars

Question 18

P. multocida strains from dogs constitute biotype characterized by ?

Answer 18

Inability to ferment mannitol but ferments maltose

Question 19

Give the Carter’s biotype of P. multocida and their corresponding features.

Answer 19

1. Mucoid
2. Hemorrhagic septicemia
3. Porcine
4. Canine
5. Feline

Question 20

On agar, P. multocida has 3 principal colonial variants. Give the type of variant with the following data:

Large, flowing, moderately virulent for mice and not typable by usual serologic methods

Answer 20

Mucoid colonies

Question 21

On agar, P. multocida has 3 principal colonial variants. Give the type of variant with the following data:

Medium sized, discrete, quite virulent for mice and typable

Answer 21

Smooth or fluorescent colonies

Question 22

On agar, P. multocida has 3 principal colonial variants. Give the type of variant with the following data:

Small, discrete, low in virulence for mice and autoagglutinable

Answer 22

Rough or blue colonies

Question 23

Mucoid and smooth colonies carry specific soluble Ags associated with _____ _____ _____, the basis of Robert’s (1947) and Carter’s (1955) classifications

Answer 23

capsular acidic polysaccharide

Question 24

What is the most prevalent capsular type among P. multocida isolates from cattle, swine, poultry, and rabbits?

Answer 24

Type A

Question 25

P. multocida is shown to carry somatic or O antigens of which there are at least ?

Answer 25

11

Question 26

Transmission of P. multocida is via ?

Answer 26

Airborne droplets or by food or water contamination

Question 27

P. multocida is a commensal of the _____ of mammals.

Answer 27

oropharynx

Question 28

Describe and give the pathogenesis of **hemorrhagic septicemia** in cattle, buffaloes, sheep and goats induced by P. multocida.

Answer 28

* Serotype B2 in Asia and serotype E2 in Africa * Disease occurs during rainy season * Animals develop high temperature **(41 to 42’C)**, dysentery, edema and in advance cases cyanosis of the mucus membranes; high mortality * **Hemorrhages** of serous surfaces, blood-stained fluid in thorax and abdomen, enteritis and edema in the subcutaneous tissues * **Edema in less acute form**; in **subacute forms lesions** confined to pectoral region which include fluid in pleural and pericardial sacs; pneumonia in lungs with greatly thickened septa * Large numbers of organism in tissues and fluid * In carrier animals organism in tonsils and pharyngeal mucosa

Question 29

Describe and give the pathogenesis of **fowl cholera** in chickens and other birds induced by P. multocida.

Answer 29

* Wild birds become infected and maybe source of infection for domestic flocks * O antigen ** types 1, 3, and 4 and capsular type A** are most prevalent * Transmission by **oral and respiratory routes, entry can be thru eye and skin** * Many cases peracute manifested by overwhelming bacteremia * Mortality **10 to 75%** * **Depression, sleepiness, inappetence and diarrhea, death within a few hours or 2 to 3 days** * P. multocida associated with chronic infections of the air sacs with accumulations of dry caseous material * Inflammatory process in the wattle especially in males which causes necrosis; infection of the mucous membranes of the head -> colds * Organisms found in peritoneal cavity of young layers mixed with the yolk from ruptured ova * Fowl cholera serious economic loss in ducks and turkeys * **Few petechiae** of heart, slightly swollen spleen, reddening of mucosa of the anterior part of intestines

Question 30

Describe and give the pathogenesis of **rabbit septicemia** in rabbits induced by P. multocida.

Answer 30

* Very acute with hardly any premonitory sign * Organisms found in film prepared from **blood or spleen pulp** after animal dies * More common form is less acute; fever, seropurulent nasal discharge, inappetence and difficulty in breathing * **Fibrinous pneumonia** with greater part of the lungs hepatized and pleura covered with fibrin deposit * Animals may not die within a few days but become emaciated and worthless afterward

Question 31

Describe and give the pathogenesis of **snuffles** in rabbits induced by P. multocida.

Answer 31

* Milder respiratory infection * Involves only **upper respiratory tract**, mucopurulent exudate which occlude the nares and conjunctiva * Difficulty in breathing with characteristic noise made by affected rabbits * **Fibrinous pneumonia** and death in some

Question 32

Describe and give the pathogenesis of **shipping fever** in sheep, swine, and goats induced by P. multocida.

Answer 32

* Contribute significantly in the morbidity and mortality * Associated with activity of certain viral infections such as **parainfluenza 3, infectious bovine rhinotracheitis, bovine respiratory syncytial virus and mycoplasma infection** * Begins a few days to a few weeks after transport *Cough, fever, nasal discharge * **Basic lesion bronchopneumonia** with moderate amount of fibrin on lung surface * Other organisms present **P. haemolytica, H. somnus or later A. pyogenes** * Associated with fibrinous pneumonia in swine, 2ndary invader in SEP, CPP, influenza, low grade fever in hog cholera * Same lung lesions seen in cattle and rabbits * Other lesions ** vegetative endocarditis, arthritis, placentitis**

Question 33

Describe and give the pathogenesis of **atrophic rhinitis** in sheep, swine, and goats induced by P. multocida.

Answer 33

* Capsular type D involved with Bordetella bronchiseptica * A **proteinaceous dermonecrotoxin** produced by type D and Type A stimulate bone resorption **Other diseases: mastitis in ewes and cows, keratoconjunctivitis in cattle, purulent leptomeningitis in dogs, septicemia in horses and donkeys**

Question 34

What are the immunization methods against P. multocida?

Answer 34

* Fowl cholera 1st bacterial disease against which a successful vaccine was prepared by Pasteur in 1880, **attenuated vaccines** * **Protective antigen** in capsule * **Bacterins** effective against hemorrhagic septicelia and fowl cholera * **Live avirulent vaccines** in drinking water in chickens, ducks and turkeys, oral and wing web * Bacterins combined with B. bonchiseptica

Question 35

What are the diagnostic methods for P. multocida?

Answer 35

1. Smears from blood or spleen, pneumonic lesion 2. Culture on BAP but not on MacConkey 3. Counterimmunoelectrophoresis to identify Ags of types B and E

Question 36

P. multocida is sensitive to what antibiotics?

Answer 36

Penicillin, ampicillin, cephalothin, chloramphenicol, gentamycin, etc

Question 37

What are diseases induced by P. multocida in humans?

Answer 37

**Animals most important source** * P. multocida, dogmatis and canis * Meningitis, abscesses, septicemia and wound infection